1. Field of the Invention
The present invention relates to the technical field of a disk device optimum for use in, e.g., an optical disk device wherein a disk-shaped recording medium, such as an optical disk, is loaded and unloaded with a disk tray.
2. Description of the Related Art
A disk device of the above type previously proposed in a prior application filed by the assignee of this application will be described below with reference to FIGS. 1 to 14. As shown in FIG. 1, an optical disk 1 as a disk-shaped recording medium is horizontally placed in a recess 3 formed on an upper surface of a tray body 2A of a disk tray 2. After that, when a tray front panel 2B of the disk tray 2 is lightly pushed in a direction of arrow a, a loading switch (not shown) is turned on. In response to the turning-on of the loading switch, as shown in FIG. 2, a loading mechanism (described later) is operated to withdraw the disk tray 2 horizontally through a tray entrance/exit opening 4 into a disk device body 6 of an optical disk device 5 in the direction of arrow a, i.e., in the loading direction, so that the optical disk 1 is automatically horizontally loaded on a disk table coupled to a spindle motor as described later.
After the loading, in response to, e.g., a recording and/or reproducing command signal from a host computer, the optical disk 1 is driven by the spindle motor to rotate at a high speed, and data is recorded on and/or reproduced from the optical disk 1 through an optical pickup. Upon receiving, e.g., an eject command signal from the host computer after the optical disk 1 has been subjected to recording and/or reproducing, the disk tray 2 is automatically unloaded through the tray entrance/exit opening 4 out of the disk device body 6 in a direction of arrow a', i.e., in the unloading direction, as shown in FIG. 1.
Next, as shown in FIGS. 3 to 9, the horizontal tray body 2A of the disk tray 2 and the vertical tray front panel 2B thereof lying perpendicularly to the directions of arrows a and a' are each formed of, e.g., a synthetic resin. An elongate bottom opening 8 is formed in the tray body 2A to extend from a central portion of the recess 3 to the side of a rear end portion (toward an end of the tray body 2A in the direction of arrow a) along a tray center line P1 parallel to the directions of arrows a and a', i.e., to the loading and unloading directions. Also, a pair of right and left horizontal guide rails 9 are integrally formed along both right and left side edges of the tray body 2A parallel to the tray center line P1. A rack 10 and a guide groove 11, which are substantially J-shaped and parallel to each other, are integrally formed in a bottom surface of the tray body 2A on one side thereof. The rack 10 and the guide groove 11 have linear portions 10a, 11a extending parallel to the tray center line P1, and arc-shaped portions 10b, 11b formed in an end portion of the tray body 2A on the same side as the front panel 2B.
A substantially box-shaped and shallow chassis 14 formed of, e.g., a synthetic resin, is provided inside the disk device body 6. The chassis 14 slides horizontally in the directions of arrows a and a' while the pair of right and left guide rails 9 on the disk tray 2 are guided by a plurality of guide ribs 15A, 15B, 15C integrally formed on inner surfaces of both right and left side plates 14a and a bottom portion 14b of the chassis 14. A vertically rotatable frame 16 formed of, e.g., a synthetic resin or metal plate, is attached onto the bottom portion 14b of the chassis 14. Insulator attachment portions 17, 18 are integrally formed in the vertically rotatable frame 16 at three positions; i.e., two in a rear end portion 16a on both right and left sides and one in a front end portion 16b at the center thereof. Three insulators 19, 20 serving as dampers, which are formed of elastic members of rubber, for example, are attached to the insulator attachment portions 17, 18.
The pair of right and left rubber-made insulators 19 attached to the rear end portion 16a of the vertically rotatable frame 16 are fastened onto the bottom portion 14b of the chassis 14 by set screws 21 which are inserted through the centers of the insulators 19, and one insulator 20 attached to the front end portion 16b of the vertically rotatable frame 16 is fastened onto a tip end of a vertically rotatable driving lever 23 by a set screw 22 which is inserted through the center of the insulator 20. The driving lever 23 is arranged perpendicularly to the tray center line P1 and is attached at its base end onto the bottom portion 14b of the chassis 14 by a pair of right and left horizontal pivot pins 24 to be rotatable in directions of arrows b and b', i.e., in the vertical direction. Accordingly, the driving lever 23 allows the vertically rotatable frame 16 to move up or down in directions of arrows c and c' upon its rotation in the vertical direction about the pair of right and left insulators 19 on the side of the rear end portion 16a which serve as fulcrums of the rotation. Additionally, a shallow recess 25 is formed in an upper surface of the vertically rotatable frame 16.
A loading mechanism 27 is attached to the bottom portion 14b of the chassis 14 on one side of the front end portion 16b of the vertically rotatable frame 16. The loading mechanism 27 comprises a loading motor 28, a pinion 29 driven by the loading motor 28 to rotate forward and backward, a pinion lever 31 causing a central shaft 29a of the pinion 29 to oscillate in a horizontal plane about a vertical pivot shaft 30 in directions of arrows d and d', a cam lever 34 driven by the pinion lever 31 through a pair of partial gears 32 to rotate in a horizontal plane about a vertical pivot shaft 33 in directions of arrows e and e', an arc-shaped cam groove 35 formed around the pivot shaft 33 of the cam lever 34 and having a level difference in the vertical direction, and a cam follower pin 36 integrally provided at a tip end of the driving lever 23 on one side thereof and loosely fitted in the cam groove 35. The pinion 29 is meshed with the rack 10 of the disk tray 2, and the central shaft 29a of the pinion 29 is loosely fitted in the guide groove 11.
The loading mechanism 27 operates such that the central shaft 29a of the pinion 29 is guided by the substantially J-shaped guide groove 11 of the disk tray 2, causing the pinion 29 to follow the substantially J-shaped rack 10 of the disk tray 2. More specifically, when loading the disk tray 2, the pinion 29 driven by the loading motor 28 to rotate forward is meshed with the linear portion 10a of the rack 10 from the side of the rear end portion of the disk tray 2 toward the side of the front end portion of the front panel 2B thereof in a linearly driving manner. The disk tray 2 is thereby withdrawn into the optical disk device 5 horizontally in the direction of arrow a. With continued forward rotation of the pinion 29 driven by the loading motor 28, the pinion 29 is oscillated in the direction of arrow d along the arc-shaped portion 10b of the rack 10. Corresponding to the oscillation of the pinion 29, the pinion lever 31 drives the cam lever 34 to rotate in the direction of arrow e through the pair of partial gears 32.
The cam follower pin 36 of the driving lever 23 is pushed upward by the cam groove 35 of the cam lever 34 in the direction of arrow b, whereupon the driving lever 23 drives the vertically rotatable frame 16 through the insulator 20 to rotate upward about the pair of right and left insulators 19 in the direction of arrow c from a descended position where the vertically rotatable frame 16 is inclined downwardly as shown in FIG. 7 to an ascended position where the vertically rotatable frame 16 is rotated up to a horizontal posture as shown in FIG. 8. When unloading the disk tray 2, the operation proceeds in a reversal manner to the loading operation. While the pinion 29 driven by the loading motor 28 to rotate backward is oscillated in the direction of arrow d' along the arc-shaped portion 10b of the rack 10, the cam lever 34 is rotated in the direction of arrow e', causing the cam follower pin 36 to move downward in the direction of arrow b' following the cam groove 35. At the same time, the driving lever 23 drives the vertically rotatable frame 16 through the insulator 20 to rotate downward about the pair of right and left insulators 19 in the direction of arrow c' from the ascended position shown in FIG. 8 to the descended position shown in FIG. 7. With continued backward rotation of the pinion 29 driven by the loading motor 28, the pinion 29 is meshed with the linear portion 10a of the rack 10 from the side of the front end portion of the disk tray 2 toward the side of the rear end portion thereof in linearly driving relation. The disk tray 2 is thereby pushed out of the optical disk device 5 in the direction of arrow a'.
A spindle motor 39 is vertically mounted within the recess 25 of the vertically rotatable frame 16 at a position near the front end portion 16b, and a disk table 40 formed of, e.g., a metal magnetic member, is horizontally fixed to an upper end of a motor shaft 39a of the spindle motor 39. The disk table 40 is integrally provided with a centering guide 40a which is formed on an upper surface of the disk table 40 at the center thereof and to which a central hole 1a of the optical disk 2 is fitted. Further, an optical pickup 41 is horizontally mounted within the recess 25 of the vertically rotatable frame 16 at a position rearward of the spindle motor 39. The optical pickup 41 has a carriage 44 to which an objective lens 42 and a light reflecting type skew sensor 43 are mounted to face upward vertically. An optical block 45 for transmitting a laser beam to the objective lens 42 is integrally attached to a side surface of the carriage 44.
A carriage moving mechanism 47 for linearly moving the carriage 44 in the directions of arrows a and a' along a pair of right and left guide shafts 46 is provided on the vertically rotatable frame 16. The carriage moving mechanism 47 comprises a pinion 50 driven by a carriage drive motor 48 through a gear train 49 to rotate forward and backward, and a rack 51 attached to one side surface of the carriage 44 and meshed with the pinion 50 in linearly driven relation. The spindle motor 39 and the objective lens 42 are arranged on the tray center line P1, and the objective lens 42 is movable in the directions of arrows a and a' along the tray center line P1.
A clamper support member 52 formed of, e.g., a metal plate, is horizontally bridged between upper ends of both the right and left side plates 14a of the chassis 14 to extend crossing above the disk tray 2. At a position right above the disk table 40, a disk clamper 53 in the form of a circular plate, which is formed of a synthetic resin and serves as a non-magnetic member, is held in a circular hole 54 formed at the center of the damper support member 52 such that the disk clamper 53 is movable within a certain range in three-dimensional directions, i.e., vertically, transversely and longitudinally. A clamper receiver 52a for receiving from below a flange 53a, which is integrally formed along an outer periphery of the disk clamper 53 at its upper end, is integrally formed along an outer periphery of the circular hole 54 in the clamper support member 52. A disk-shaped magnet 55 is horizontally embedded in an upper central portion of the disk clamper 53. A later-described upper cover 62 formed of a metal plate and serving as a magnetic member is attached to the top of the chassis 14 to extend over the clamper support member 52.
Accordingly, en shown in FIG. 8, when the optical disk 1 is loaded with the disk tray 2 into the disk device body 6 horizontally in the direction of arrows a and the vertically rotatable frame 16 is then moved up in the direction of arrow c to the horizontal ascended position, the disk table 40 is inserted upward through the bottom opening 8 of the disk tray 2 and the centering guide 40a of the disk table 40 is fitted to the central hole 1a of the optical disk 1 from below. With the fitting of the disk table 40, the optical disk 1 is floated upward within the recess 3 of the disk tray 2, and simultaneously the disk clamper 53 is slightly floated upward from the flange receiver 52a of the clamper support member 52. At this time, the disk clamper 53 is attracted onto the disk table 40 by magnetic attracting forces of the magnet 55 in the disk table 40 which is now positioned close to a lower surface of the disk clamper 53, so that the optical disk 1 is chucked onto the disk table 40 horizontally with the aid of the disk clamper 53.
In response to, for example, a recording and/or reproducing command signal from a host computer, the optical disk 1 is driven by the spindle motor 39 to rotate at a high speed, and the carriage 44 of the optical pickup 41 is moved by the carriage moving mechanism 47 in the directions of arrows a and a', causing the objective lens 42 to move in the directions of arrows a and a' along the tray center line P1. Then, a laser beam transmitted from the optical block 45 is irradiated to a lower surface of the optical disk 1 through the objective lens 42, and light reflected from the optical disk 1 is received by the optical block 45 through the objective lens 42. As a result, data is recorded on and/or reproduced from the optical disk 1.
In this connection, the carriage moving mechanism 47 operates such that the pinion 50 driven by the carriage drive motor 48 through the gear train 49 to rotate forward and backward is meshed with the rack 51 in linearly driving relation, and the carriage 44 is moved in the directions of arrows a and a' along the pair of right and left guide shafts 46. Upon receiving, e.g., an eject command signal from the host computer after data has been recorded on and/or reproduced from the optical disk 1, the vertically rotatable frame 16 is moved down to the descended position in the direction of arrow c and the disk table 40 is dechucked from the disk clamper 53 to move away from the optical disk 1 downward. Following that, the optical disk 1 is horizontally placed in the recess 3 of the disk tray 2 and then unloaded out of the disk device body 6 horizontally in the direction of arrow a', as shown in FIG. 7.
In the unloading condition of the optical disk device 5, as shown in FIG. 7, the disk clamper 53 is lowered by its own weight and is suspended while the flange 53a along the outer periphery of the disk clamper 53 is held in abutment with the flange receiver 52a of the damper support member 52. In this suspended state, a clearance L2 is secured between the lower surface of the disk clamper 53 and the optical disk 1 on the disk tray 2 so that the optical disk 1 does not interfere with the disk clamper 53 when the optical disk 1 is loaded and unloaded. In the unloading process of the optical disk device 5, therefore, the disk clamper 53 is lowered from the clamper support member 52 by a clearance L2, and the clearance L1 must be secured between the disk clamper 53 and the optical disk 1. Thus, a relatively large space corresponding to L1+L2 is present between the lower surface of the clamper support member 52 and the upper surface of the optical disk 1.
As shown in FIGS. 6 and 9 to 12, a disk tray guide mechanism for horizontally sliding the disk tray 2 in the directions of arrows a and a' with respect to the disk device body 6 comprises a pair of right and left slide guide grooves 12 formed in bottom surfaces of the pair of right and left guide rails 9, which are provided on the tray body 2A of the disk tray 2, and extended parallel to the tray center line P1, a plurality of main and sub-guide ribs 15A, 15B which are integrally formed on the bottom portion 14b of the chassis 14 to lie in two lines parallel to the tray center line P1 at positions near both right and left side ends thereof and are engaged with the pair of right and left slide guide grooves 12, and a plurality of floating-preventive guide ribs 15C integrally formed on the inner surfaces of both the right and left side plates 14a of the chassis 14 in match with top positions of the pair of right and left guide rails 9.
More specifically, two main guide ribs 15A for not only avoiding wobbling movement of the disk tray 2 in a transverse direction (direction of arrow g) perpendicular to the longitudinal direction of the disk tray 2, i.e., to the directions of arrows a and a', but also restricting the height of the disk tray 2 are arranged on one of the right and left sides of the chassis 14 at a position near the tray entrance/exit opening 4, which is formed in the front panel 60 of the disk device body 6, to lie in one line with a small spacing L11 therebetween in the longitudinal direction (the directions of arrows a and a'). Also, two sub-guide ribs 15B for restricting the height of the disk tray 2 are arranged on one of the right and left sides of the chassis 14 to lie in one line between a position behind the two main guide ribs 15A and a rear panel 61 of the disk device body 6. Further, four sub-guide ribs 15B are arranged on the other of the right and left sides of the chassis 14 to lie in one line between the front panel 60 and the rear panel 61 of the disk device body 6. Both the slide guide grooves 12 have widths W1 equal to each other, and a width W2 of each of the two main guide ribs 15A in the direction of arrow g is substantially equal to (exactly, a little smaller than) the width W1 of both the slide guide grooves 12. A width W3 of each of the sub-guide ribs 15B in the direction of arrow g is fairly smaller than the width W1 of both the slide guide grooves 12.
With the disk tray guide mechanism thus constructed, even if tolerances of the disk tray 2 and the chassis 14 are set to be relatively large when molded of a synthetic resin, the disk tray 2 can be smoothly loaded and unloaded in the directions of arrows a and a' between the unloaded position shown in FIG. 10 and the loaded position shown in FIG. 11 because the two main guide ribs 15A serve to rather avoid the disk tray 2 from wobbling in the width direction of the disk tray 2 (the direction of arrow g) and the main and sub-guide ribs 15A, 15B serve to restrict the height of the disk tray 2. When the disk device body 6 is used in a normal horizontal posture, the disk tray 2 is stably horizontally rested on the main and sub-guide ribs 15A, 15B by its own weight, and therefore the plurality of floating-preventive guide ribs 15C develop no function. On the other hand, when the disk device body 6 is used in a vertical posture, or when the optical disk device 5 is inverted upside down, the plurality of floating-preventive guide ribs 15C function as ribs for preventing tilting and falling of the disk tray 2.
FIGS. 13 and 14 show a computer body 111 of a computer apparatus 110. Inside a front panel 11a of the computer body 111, a plurality of recording/reproducing devices, such as the above-mentioned optical disk device 5, a floppy disk device 112 and a hard disk device 113, are incorporated in vertical multiple stages. Further, a ventilation fan 114 is incorporated in a rear panel 111b (or side panel) of the computer body 111 to discharge air in the computer body 111 to the outside in the direction of arrow h. The interior of the computer body 111 is thereby forcibly cooled to avoid a rise of temperature in the computer body 111.
FIG. 14 shows a casing of the disk device body 6 of the optical disk device 5 incorporated inside the front panel 111a of the computer body 111. The casing of the disk device body 6 is in the form of a flat box built up of the front panel 60 which is formed of a synthetic resin and has the tray entrance/exit opening 4 formed therein, the rear panel 61 integrally formed at a rear end of the chassis 14, and upper and lower covers 62, 63 formed of metal plates and fixedly fitted respectively to the top and bottom of the chassis 14 with screws. In addition, printed boards 64, 65 are fixed to the bottom of the chassis 14 with screws from below to extend horizontally. A gap 67 is left between the printed boards 64, 65 and the lower cover 63 to avoid contact between the lower cover 63 and a plurality of electronic circuit elements 66 mounted to lower surfaces of the printed boards 64, 65.
As shown in FIG. 2, an eject button 68, an emergency hole 69, an earphone jack insertion hole 70, a volume control 71, etc. are disposed on the front panel 60 below the tray entrance/exit opening 4 to lie in a horizontal line. Of course, as shown in FIGS. 13 and 14, the eject button 68, the emergency hole 69, the earphone jack insertion hole 70, the volume control 71, etc. are exposed to a front surface of the front panel 111a of the computer body 111. When a computer user pushes the eject button 68 by a finger, the disk tray 2 can be unloaded at any time. In case of emergency such as a power failure, when a computer user pushes a thin rod-like member into the emergency hole 69, the cam lever 34 shown in FIG. 3 is rotated in the direction of arrow e, allowing the disk tray 2 to be manually unloaded. Also, when a computer user desires to listen sounds from a CD, an earphone jack is inserted into the earphone jack insertion hole 70 and the volume of sounds is adjusted by the volume control 71.
As shown in FIGS. 13 and 14, therefore, when the ventilation fan 114 in the computer apparatus 110 is operated to discharge air in the computer body 111 to the outside, a negative pressure is developed in the disk device body 6 of the optical disk device 5, whereby open air is sucked into the disk device body 6, through a gap between an inner periphery of the tray entrance/exit opening 4 and the tray front panel 2B, as well as gaps left in an attachment hole of the eject button 68, the emergency hole 69, the earphone jack insertion hole 70, an attachment hole of the volume control 71, etc.
The optical disk device 5 previously proposed is however still problematic in the following point. As mentioned above, when the ventilation fan 114 in the computer apparatus 110 is operated to discharge air in the computer body 111 to the outside, a negative pressure is developed in the disk device body 6 of the optical disk device 5, whereby open air is sucked into the disk device body 6 through gaps left in the tray entrance/exit opening 4, in the attachment hole of the eject button 68, the emergency hole 69, the earphone jack insertion hole 70, the attachment hole of the volume control 71, etc., as indicated by arrows in FIG. 14. Accordingly, dirt and dust in open air are also sucked into the disk device body 6 together with the open air. If dirt and dust sucked into the disk device body 6 adhere to the recording and/or reproducing surface of the optical disk 1, or adhere and deposit onto the disk table 40 and the objective lens 42 of the optical pickup 41, the presence of dirt and dust may impede irradiation of the laser beam to the optical disk 1 and reception of the reflected laser beam from the optical disk 1, or may incline the optical disk 1 in a state chucked on the disk table 40, thus causing, e.g., a failure in focusing of the laser beam. As a result, there may occur an error in recording and/or reproducing (a failure in writing and/or reading) of data on and from the optical disk 1. Also, if dirt and dust sucked into the disk device body 6 adhere and deposit onto, e.g., the guide shafts 46 and the gear train 49 of the carriage moving mechanism 47, the movement of the carriage 44 is adversely affected and such a problem as causing a trouble in seek and tracking is more likely to occur.